Reinforced pipe joint



Feb. 26, 1957 R. P. STAMBAUGH EI'AL 2,82,0

REINFORCED PIPE JOINT Filed Feb. 17, 1954 Pores Filledi Wiih Thermosethng Resin Carbopaceous Pipe Fabric Bonded To Pipe Thermosefling I Cemeni Pores Fi lied With carbonaceous -Thermosei'hng Resin Pipe Fabric Bonded To Pipe Thermoseifing Carbonaceous Cement Fitting \JHI INVENTORS WILLIE H. WATTS R0 P. s MBAUGH ite States REINFORCED PIPE JOINT' Robert P. Stambaugh, Grand .Island,'N; Y'., and. Willie H. Watts, Avon; Lake; Ohio, assignors ;to. Union. Carlggidekand Carbon Corporation, a corporation of New Application February '17, 1954, SeriaLNo. 410,931

9 Claims, (CL l3 8-7 6) This invention relatesioa-high strength connection between carbonaceousarticles. More particularly, this invention relates toreinforced assemblies .of fabric-bonded, resin-impregnated carbonaceous: pipe and resin-impregnated carbonaceous fixtures.

Fragilepipe or tubingsuch.as-carbonaceous piping of tageous properties, thefluid. perviousness has been over-- come by introducing. resinsinto .the pores of thepipe and converting such resins, into solids, as is known in the art. But,- inthe. present status ofthe art, theresstill remains the lowmechanical strength, for although the mechanical strength is 1 somewhat improved a by such resin. treatment, the resulting product is brittle and susceptible.

to shattering froma. shock or blow. This inherentfragility presentsa problem thus far. unsatisfactorily solved.

Further, this inherent. fragility. manifests itself particularly at the joints between the pipe and fixturesv suchas.

flanges, elbows, etc. The normal. practice is to. join the pipe-and fixtureby means of :threading and a cementing agent. The joints however are of unsatisfactory strength for it is-well established: in thetheory; of stress. concentrations that=irregularities in. a-. loaded member such as.

holes, notches, grooves, etc., are points-oflocalized stress at which the. stresses are considerably. greater than the.

average stresses. Whilethese particular stresses are undesirable instronger materials, theybecomev critical in brittle carbonaceous products; In.-- the. example. set. forth above, the critical area is the basethread. In the assem-,

blies of the invention, the. ultimate strength advantage --is gained from. the thigh tensiler'strength of the 1 bonded fabric covering.

In our copending application, Serial No. 410,930 filed February 17, 1954, and assigned to the assignee of this invention, we h'ave described and claimed-an article, and the method of itsfabrication, comprising-, in combination, a carbonaceous pipe, a closely fitting fibrous sle eving, and an infusible bonding resin, or resin s, the article having fluid impreviousness and high'mechanicalstrength,

It isan object of this invention to provide assemblies between vresin;impregnated,' fabric-bended, carbonaceous pipe. and resin-impregnated" carbonaceous fixtures, -said assembliesbeing fluid-impervious and ofhigh mechanical strength.

The invention by means of which these objects are achieved comprises, in combination, assemblies of fabricbonded, resin-impregnated carbonaceous pipe fitted into a resin-impregnated carbonaceous flange, and a cementing agent. The assemblies may be constructed without the use of threads, the flange being counterbored to receive the pipe, in which construction the fabric bonding extends to the bottom of the counterbore; alternatively 2,782,805 Patented Feb. 26, 1957 he assembly. ma be, nst a ed ithz hepip ndfiasse.

hre a io s m shwa he a cb d na s tends into the counterbore only to the depth wherelthezthreaded portion begins,

In the. accompanyingdrawing:

Fig. 1 is a partially cut away, vertical section of an;

se ly. emb d in th inv n on.

Fig. 2;is,a partially cut-away, vertical section of an other embodiment of an assembly according to the-in.

vention.

Withreference to the drawing, the assembliesof the invention comprise,-as shown in Fig. 1, one embodiment,

of the ,invention, a fabric-bonded, resin -impregnatedca1;

mating surfaces; an annular space maybe provided at the; upper end of said, flange-providing a reservoirfor; said-.ceinentingagent, Anotherembodiment of an assembly; according to the invention, as shown in Fig. 2, comprises a fabric-bonded, resin-impregnated carbonaceous pipe threadably fitted into a counterbored, resin-impregnated carbonaceous flange, the fabricbonding extending;

intothe counterb'ore to the depth Where the threaded portion begins, all mating surfaces being held together;

with an infusible, resinous, carbonaceous cementing agent;

an annular space maybe provided at the upper end of said flange, providing a reservoir for said cementing agent.

A preferred method of making assemblies of fabric.

bonded, resin-impregnated carbonaceous pipe-and resinimpregnated fittings such as flanges according to the invention, isset forth as follows:

length of resin-impregnated, carbonaceous pipe is threaded into a threaded, counterbored resin-impregnated carbonaceous flange, the threaded areas of each being first painted with a wetting agent, for example, furfuryl aloohol and then coated with a cementing agent containing'aasynthetic resin capable of being converted to;

aninfusible solid. A cementing; agent that has given sat-.

isfactoryresults has-the composition, by weight: 10 0 partsthermosetting, phenol-formaldehyde resin and 30;

parts cokeflour. A section; of woven, fibrous glass sleev-. ing isslipped over the pipe. and brought down approximately-.even--with thelbase-thread of the pipe, the sleeving being held in place at either end of the pipe by means of hose clamps. A cement head is then laid in the flange counterbore,-- after which the lower hose clamp is removed. Tlie-sleeving-encasecl pipe-is then brushed until saturated witha thermosettingresin washcoat. A coating thathas given satisfactory'resnlts has-the composition, by weight; 100 parts: thermosetting, phenol-formaldehyde resin, 1 part lampblack, and acetone suificient to form a thin brushing-solution The -assembly is aged for about 4 hours at room temperature, then cured for about 12 hour s;at-;about (3., the heat beingprovided by infra red lamps.

An alternate method that, has givensatisfactory results comprises. the sarne steps, as set; forth above except that the ;pipe.=.andflange are not threaded. In; this alternate methodsthe-sleeving extendsdown the-full length of thev dehyde resins. Sleeving of forms other than woven and of mateials other than glass may be used, as may any resin capable of binding the sleeving to the carbonaceous pipe. Other materials will readilybe s ggested to thoseskilled in the art, all coming within the scope of the invention. p

Demonstrating the success of the invention, when cantilever loads are applied to 2 inch (l /i'inches inside diameter) resin-impregnated carbonaceous pipe, having the conventional threaded, cemented connection, typical failures occur at loads from 200-500 pounds applied 6 inches from the joint. Joints of the invention, threadably assembled, raised the breaking load up to 700 pounds, an increase of 50%. When the fitting is assembled with out the use of threads, the fitting did not fail at loads of 1200 pounds. As an added demonstration, the fittings were repeatedly dropped to a cement surface from a height of twenty feet without developing fractures. Final breakage was achieved only when the fittings were fixed in a vise and struck repeatedly with a hammer, the rmture then occurring only at the point of impact.

From the above description it will be seen that high strength characteristics may be imparted to a carbonaceous fitting comprising a carbonaceous pipe and a carbonaceous flange, which under ordinary circumstances would be readily subsject to fracture. This is accomplished by bonding a fabric covering to the pipe and inserting the pipe end into the flange. The flange and pipe are loosely fitting, and may or may not be provided with loosely engageable thread parts. A cementitious material is then introduced into the clearance space between the pipe and the flange to hold them in assembled relation.

It is to be understood that the term carbonaceous or carbon as used in this specification is intended to include graphite as well as amorphous carbon.

What is claimed is:

1. An assembly for carbonaceous pipe comprising, in combination, a fabric-bonded, resin-impregnated, carbonaceous pipe; a resin-impregnated carbonaceous flange member having opposite faces and a stepped-diameter boring having a relatively large diameter section and a relatively small diameter section axially aligned therewith, said relatively small diameter section passing through said flange member, said relatively large diameter section adapted to receive said carbonaceous pipe in a relatively loose fitting thereby providing a small annular space between said carbonaceous pipe and the internal surface of said large diameter section of said boring; and an infusible, resinous cementing agent in said annular space to firmly hold said carbonaceous pipe therein.

- 2. An assembly for carbonaceous pipe comprising, in combination, a fabric-bonded, resin-impregnated carbonaceous pipe; a resin-impregnated carbonaceous flange member having opposite faces and a stepped-diameter boring having a relatively large diameter'section and a relatively small diameter section axially aligned therewith, said relatively small diameter section passing through said flange member, said relatively small diameter section and said pipe being correspondingly threaded to interfit loosely and define therebetween a clearance space, and an infusible, resinous cementing agent in said space to firmly hold said pipe and flange in fixed relation.

- 3. Anassembly for carbonaceous pipe comprising, in combination, a fabric-bonded, resin-impregnated, carbonaceous pipe; a resin-impregnated carbonaceous flange member having opposite faces and a stepped-diameter boring having a relatively large diameter section, arelatively smaller diameter section and a relatively small diameter section, said relatively small diameter section passing through said flange member, said relatively smaller section adapted to receive said carbonaceous pipe in a relatively loose fitting thereby providing a small annular space between said carbonaceous pipe and the internal surface of said smaller diameter section of said boring, said relatively large diameter section forming an annular trough between said carbonaceous pipe and the internal surface of said large diameter section of said boring; and a carbonaceous cementing agent in said annular space and in said annular trough.

4. An assembly for carbonaceous pipe comprising, in combination, a fabric-bonded resin-impregnated, carbonaceous pipe; a resin-impregnated carbonaceous flange member having opposite faces and a stepped-diameter boring having a relatively large diameter section, a relatively smaller diameter section and a relatively small diameter section, said relatively small diameter section passing through said flange member, said relatively smaller section and said pipe being correspondingly threaded to interfit loosely and define therebetween a clearance space,

said relatively large diameter section forming an annular trough between said carbonaceous pipe and the internal surface of said large diameter section of said boring; and an infusible, resinous cementing agent in said space and in said annular trough.

5. A heat resistant, corrosion resistant fitting having relatively high strength characteristics, said fitting comprising a carbonaceous tube, a carbonaceous flange loosely receivable on said tube and defining a clearance space therebetween, a fabric sheath disposed around said tube in fixed and adjacent relation thereto, said sheath having a portion thereof extending into said clearance space, and a cementitious material filling said clearance space and being in contact with portions of said tube, sheath and flange, thereby holding said fitting in assembled relation.

6. In the fitting of claim 5, the portion of said tube in contact with said cementitious material and the cementcontacting portion of said flange having complementarily formed threads.

7. In the fitting of claim 5, said tube and sheath terminating flush with each other and in spaced relation to said flange.

8. In the fitting of claim 6, the threaded portion of said tube extending beyond said sheath portion.

9. A high strength fitting comprising a tube of normally fragile material, a flange of normally fragile material loosely receivable on said tube and defining a clearance space therebetween, a fabric sheath disposed around said tube in fixed and adjacent relation thereto, said sheath having a portion thereof extending into said clearance space, and a cementitious material filling said clearance space andbeing in contact with portions of said tube, sheath and flange, thereby holding said fitting in assembled relation.

References Cited in the file of this patent UNITED STATES PATENTS 507,040 Rassbach Oct. 17, 1893 1,065,495 Aylsworth June 24, 1913 1,876,586 Austin Sept. 13, 1932 1,931,311 Young Oct. 17, 1933 2,089,802 Kirby Aug. 10, 1937 2,238,462 Crepeau Apr. 15, 1941 2,431,633 Brown Nov. 25, 1947 

1. AN ASSEMBLE FOR CARABONACEOUS PIPE COMPRISING, IN COMBINATION, A FABRIC-BONDED, RESIN-IMPRAGNATED, CARBONACEOUS PIPE; A RESIN-IMPREGNATED CARBONACEOUS FLANGE MEMBER HAVING OPPOSITE FACES AND A STEEPED-DIAMETER BORING HAVING A RELATIVELY LARGE DIAMETER SECTION AND A RELATIVE SMALL DIAMETER SECTION AXIALLY ALIGNED THEREWITH, SAID RELATIVELY SMALL DIAMETER SECTION PASSING THROUGH SAID FLANGE MEMBER, SAID RELATIVELY LARGE DIAMETER SECTION ADAPTED TO RECEIVE SAID CARBONAEOUS PIPE IN A RELATIVELY LOOSE FITTING THEREBY PROVIDING A SMALL ANNULAR SPACE BETWEEN SAID CARBONACEOUS PIPE AND THE INTERNAL SURFACE OF SAID LARGE DIAMETER SECTION OF SAID BORING; AND AN INFUSIBLE, RESINOUS CEMENTING AGENT IN SAID ANNULAR SPACE TO FIMLY HOLD SAID CARBONACEOUS PIPE THEREIN. 